Cu-Pd alloy electrocatalysts with enhanced performance and stability in direct formaldehyde fuel cells

Copper-based materials are promising for formaldehyde oxidation to produce hydrogen but suffer from degradation caused by soluble copper ions in alkaline electrolytes. In this report, a novel Cu_1.2Pd_0.8/CC alloy electrocatalyst is developed to address this issue. The catalyst drives formaldehyde oxidation at 0.2 V to produce a current density of 50 mA cm^-2. Stability tests over 100 h show no significant decay in current density, and the copper ion concentration in the solution remains low at 10.7 μg L^-1, almost ten times lower than that observed with copper foam electrodes under identical conditions (107.1 μg L^-1). When used in direct formaldehyde fuel cells, the catalyst achieves an open-circuit voltage of 0.9 V and a peak power density of 100.0 mW mg_Cu^-1. This study provides a new strategy for enhancing copper-based catalysts through alloying.